Air filter



FIG. 1 is a front plan view of an air filter, showing my new design;

FIG. 2 is an enlarged detail view of portion 2 of FIG. 1 ;

FIG. 3 is a top plan view thereof;

FIG. 4 is an enlarged detail view of portion 4 of FIG. 3 ;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is an enlarged detail view of portion 6 of FIG. 5 ;

FIG. 7 is a rear plan view thereof.

FIG. 8 is an enlarged detail view of portion 8 of FIG. 7 ;

FIG. 9 is a left plan view thereof;

FIG. 10 is a right plan view thereof; and,

FIG. 11 is a left ,perspective view thereof.

The evenly spaced broken lines depict portions of the air filter that form no part of the claim.

The dash dot dash broken lines indicate cutoff boundaries for enlarged detail portion views and form no part of the claim. 

CLAIM The ornamental design for an air filter, as shown and described. 